Control device



May 25, 1937- w. L. HxcKs-Tr-:IlN x-:T Al. Re. 20,380

CONTROL DEVICE Original Filed Dec. 12, 1930 Reissueil May 25, 1937 NToEEicE CONTROL DEVICE vWilliam L. Hickstemlrvington, and Edwin C.Loesser, Glen Ridge, N. J

Original No. 1,985,659,

Serial No. 501,983,

dated Decembery 25, 1934, December 12, 1930. Ap-

plication for reissue December 24, 1936, Serial 34 Claims.

This invention relates to control devices which may ygovern mechanism ofany type. In the particular embodiment we have illustrated, theinvention is applied to an oil burning steam heater as our firstcommercial devices were used in connection with that mechanism. Theinvention, however, is of broad scopev and may either shut off orinitiate the movement of any chosen mechanism or it may operate a makeand break device and in the latter case obviously some installationswill require that the current be broken whereas other quite similarinstallations will require that'under the same conditions the circuit becompleted. The primary object of this invention is to provide a devicethat will operate 'in some fashion entirely automaticallyand in responseto either of two movements substantially at right angles to each otheror to the combined movements. A second and important object of thepresent invention is the provision of an automatic switch which will beoperated by a horizontal movement of the control device to open or closethe switch and in addition will be operated to open or close the deviceindependently of the rst movement if the control rod be moved in adifferent direction.

A still further object of the present invention lies in the provision ofan automatic device for control of the motor of an' oil burner by eitherchange in pressure or change in -water level or both. v

In many installations it is common to cut 01T the heat when the steampressure or the temperature reaches some chosen maximum point and toturn on the heat either by moving a valve or starting a motor when somechosen minimum is reached and the installation generally contains inaddition a separate switch which closes the valve or stops themotorwhenever the water level sinks below'a certain chosen point. While thetwo devices working together are very common ythere is no simple compactautomatic control unit for accomplishing both purposes.

In the drawing:-

Figure l is a side elevation partly broken away.

Figure 2 is an end view of the preferred apparatus as shown in Figure 1but with the cap removed.

Figure 3 is a sideelevation of a modified form.

Figure 4 is a still further modification.

Figure 5 is an end view of the switch cradle.

Figure 6 is a plan ofv the contact members shown in Figure 4.

In the preferred form shown inFigures l and 2, the device consists in alcasting III having a steam inlet nipple II and a Water inlet I2, theformer in communication with the steam chamber of the boiler and thelatter in communication with the water which is being heated. Thepressure in the chamber I3 will, therefore, be the 5, same as thepressure in the steam line and the entire device is so located that thechosen water level is at the longitudinal center line of the cylindricalcasting I 0.

To the open end ci.' the casting I0 is secured a lo disk I4 permanentlycarrying a corrugated metal` cylinder I5 hereinafter called the bellows.The circular end IB of the bellows is preferably of slightly heaviermetal than the corrugated por' tion and, this disk carries centrally abearing or collar I1 and carries near its periphery a float I8. Whileobviously the float I8 may be spaced away from the bellows as in ourearlier models, we find it convenient to build the float in the shorttest tube form illustrated and to fasten it securely and permanently tothe bellows and also to the rod 20 which nts rather snugly in thebearing or collar II on the wall I6.

From the above it will be seen that the chamber I3 is fluid' and liquidtight and that when the steam pressure entering thru port II increasesthe bellows will be made shorter and since the bellows carries the floatand the rod 20 is attached to theA iioat at its far end any increase ofpressure will move the rod 20 in an axial direction and any decrease inpressure, augmented, if 3 desired, by the optional helical spring 2|which we nd unnecessary with the rather low pres-I sure encounteredinoil burning heaters, the rod 2|) is moved horizontally to the right asseen in Figure 1. A further and totally independent movement of the rod-follows changes in the y water-level. As illustrated the water level isat the desired height. Should the water level sink in thek main devicethe water level in chamber I3 A o would respond at once and the oat 20would fall but since the bellows is fast to the closure disk Il the rod20 will turn about an axis located be,- tween the wall 'I4 and the wallI8, the location of this axis changes with the amount of compression ofthe bellows. The bellows. being readily bendable, will permit thenecessary tilting of the end wall I6 as will readily be understood bythose familiar with these elements. It will thus be seen that thecentral rod 20 will move axially in response to pressure changes andwill tilt about some intermediate point in response to water levelchanges. In other words, the float has universal movement.

In the preferred form the object which is oontrolled by movement of therod is an electric make and break apparatus of the mercury type known inthe trade as a mercoid switch. This tube is given the numeral 22 andreceives its currents thru wires 23 leading to an outlet box 24. Whilethe tube itself is of well-known commercial form its mounting is novel.The removable end wall I4 of the pressure chamber carries the outlet boxat the bottom. and two parallel brackets 25 at the top, the free ends ofwhich are connected by a pivot rod 2B on which is swung a cradle 21which is merely a strap of material preferably spring metal to embracerather rmly the tiltable mercury tube switch element 22. At each sideand diametrically of the tube is an. outwardly extending lug 28positioned so as to be engaged by a rather heavy wire frame 38adjustably carried on the control rod 28. We prefer to have theengagement between the lug 28 and the frame 38 adjustable because inthis way we can use the same device for many different types ofinstallation. A very convenient way of achieving this purpose is lbyhaving a portion of the control rod 28 threaded and on this threadedportion we locate a nut 3l having an extended sleeve 32 which isannularly gr'ooved to receive the nearly circular end 33 of the forkframe 38. The frame being of spring steel can be adjusted manually afterthe nut is correctly set so as not to engage either the tube or thesides of the cradle 21 and preferably the nut 3| would be held in chosenposition by some positive means such as the lock nut 34. Upon decreaseof pressure in the chamber I3 the rod 28 moves to the right and thespace between the lug 28 and the vertically standing arms of the fork 38increases. When, however, the pressure increases within the chamber theentire rod is moved to the left and at the chosen pressure the framestrikes the two lugs 28 and tilts the mercury tube switch element 22about its `pivot 26 and this act causes the current to be broken if thetwo contacts in the mercoid tube are near the left hand edge or causethe current to be made if the contact should be in the other end of thetube. As illustrated the contacts are in the left hand end and thepressure breaks the electric current which in this case goes to themotor and the stopping of the motor in turn cuts 01T the supply ofliquid fuel. When the pressure or temperature decreases the bellows I5expands and the current is again completed to the motor.

I'he same mercury tube switch element 22 responds independently to a.change in. water level. The control rod 28 at its extreme .left handedge isbentv upwardly`as at 36. We do not nd it necessary to fork thisend but the rounded free end strikes the tube at its lowest point andwith pressure changes merely slides horizontally on the tube having noeffect whatsoever upon it. Should the water level drop, however, the end36 of the control rod is elevated and this tilts the mercury tube 22 inexactly the same way as does i the engagement between the frame 38 andthe lugs28. It will be noted that the upturned end 36 of the control rodalso acts as a stop for the switch.v Except for this provision it wouldbe necessary to have some means for preventing the heavier left hand endof the tube moving downwardly.

In Figure 3 the casing is made in two parts I8EL and I8b binding betweenthem in fluid tight manner a circularly corrugated disk 40 to which thecontrol rod 28a is permanently secured. The float I8 in this case isspaced from the diaphragm disk 48 but the-operating mechanism in theleft hand space is identical and, as in the preferred form, it iscovered by a readily removable light cap 4I which may, if desired, be ofglass or other transparent material. In Figure 4 ,the mercury switch isreplaced by a pair of spaced terminals 44 which are bridged to completethe circuit by the upturned end IIIb of the control rod 28h. The frame38 has its' counterpart in. a cam surface 45 which presses two springleaf terminals 44 downward into contact with an electrically conductingbridging member 46 carried on the control rod preferably in anadjustable man ner as by the nut 3l?. In this modification the member 41m'oves horizontally in accordance with some change in conditions as, forexample, a change in pressure. The rod carries a plate 48 which mayengage a roller 49 on the control rod which is spring pressed againstthe plate 48 so as to move the control rod horizontally against thespring. The member 58 corresponds to the float and it moves verticallyin accordance with some change in conditions as, for example, the waterlevel. This member 58 ends in a ring 5I which rather snugly embraces thecontrol rod which slides freely in a spherical bearing 52 set in a wall|41. As in the other modifications the circuit is completed or is brokenas may be desired upon a movement of the member 41 in one direction andby a movement of the member 58 in a direction at right angles to themovement of the member 41.

Referring again to Figure 1 it will be seen that in the preferredembodiment of our invention We have produced a float having completelyuniversal movement and one that is of economical design and may be made,installed and repaired at the expense of minimum time and labor.

What we claim is:

1. A device operated by changes in water level and pressure, comprisinga fioat, a pressureA re-l sponsive element secured to said float, meansactuated by the float in response to changes in liquid level, said meanssov connected to the pressure responsive element as to be actuatedthereby independently of the liquid level changes.

2. In combination, a float, a pressure responsive device, an operatingelement, a mercury switch tube and a cradle therefor, said tube andlcradle forming a pivoted crank of which the tube is the substantiallyhorizontal arm and the cradle is the substantially vertical arm, saidoperating element being pivotably 'supported by the pressure responsivedevice and so connected to the float as to be actuated by changes inliquid level, the operating element being positioned to move against thevertical arm of the suspended crank when actuated by the pressureresponsive device, and

positioned to move against the horizontal tube when actuated about itspivot by the float.

3. A bellows and a float xedly secured thereto in combination with a rodto produce a movement of one end thereof in two directions normal toeach other.

4. A diafragm and a float in combination with one end vof`a rod toproduce a movement of the other end of the rod in two directions normalto each other. Y

5. The combination with a member to operate a control device, ofactuating means to move the member in one direction in accordance with achanged condition, and a second actuating means iixedly secured to saidfirst mentioned means to move the member at an angle to such directionin accordance with a different changed condition.

6. In a device for completing an electrical circuit, a rod, a bearing inwhich the rod is slidably and pivotally supported,v and means located onone side of said bearing moving substantially normally to each other formoving the rod in and about its bearing.

7. In a pressure operated switch controlling device, a pivoted cradleapressure responsive member, a rod connected to said member, a camadjustably secured on said rod to tilt the cradle upon increase ofpressure, and means at the end of the rod for holdingthe cradle athorizontal.

8. In combination, a cylindrical bellows compressible under pressure, aiioat secured to the bellows, and a rod fast to the float and passingaxially thru the bellows.

9. In combination, a corrugated metal pressure responsive cylinderclosed at one end, 'a perforated wall supporting the cylinder at theother end in uid tight fashion, a rod passing thru the hole in the walland passing axially thru the cylinder, and .a iloat secured to the freeend of the rod.

10. In combination', a chamber adapted to be I placed in communicationwith a iluid reservoir and a pressure system, a pressure responsivediafragm closing one side of saidchamber, a member pivoted to saiddiafragm and a float secured to the member and lying within the chamber.

l1. In a switch, a pair of contacts, a bridging member mounted to ljoinsaid contacts upon lowering of a water level, a second bridging memberand pressure responsive means to cause the second bridging member to.join said contacts.

12. In combination, a chamber having a steam port and a water port, afloat within said chamber, a pivoted lever carrying said float,pressurev responsive means for moving the pivot of the lever inhorizontal direction, a tiltable member supported by the lever, andmeans for translating the sliding movement of the lever into tiltingmovement of the member independently of the support given the tiltablemember by the lever.

13. In combination, a rod adapted to open and close an electric switch,means responsive to pressure changes tomove the rod, and a float securedto said rod to move the rod in response to changes in liquid level.

14. An electric switch, a rod, a pressure responsive member secured-tosaid rod to move the rod axially to operate said switch, andra floatdirectly secured to said rod to operate said switch in accordance withliquid level changes.

l5. A switch operating unit consisting of means responsive to liquidllevel changes and means responsive to pressure changes, and a switchengaging member rigidly secured to both of said means to move constantlytherewith.

16. In combination, a member having a free end adapted to be operativelyconnected to a desired mechanism, actuating means located at axeddistance from said free end and responsive .to'

liquid level changes for moving the free end of said member, and meansresponsive to pressure changes to move the free end of the member, saidrst mentioned means being so connected to said member as to maintainsaid nxed distance during all changes in pressure and liquid level.

17, In combination, a chamber having an opening in one wall, a pressureresponsive device sealing said chamber, a rod centrally pivoted in saiddevice, a oat within the chamber and secured to one end ofthe rod, thefree end of said rod extending thru said opening, a switch adjacent tosaid free end and adapted to be operated thereby said rod extending fromysaid v upon movement of the rod by pressure on the device or by changein water level in said chamber. 18. A combined pressure and floatactuated switch mechanism for boilers, comprising a cas- Y.ing havingmeans for communicating with the interior of a boiler above and belowthe water level thereof, an electric .switch mechanism including amercury tube `switch and operating means for throwing the switch tube toopen and closed positions, an expansible and contractible 10 memberwithin the casing and` connected to said switch operating means .wherebya change of pressure in the casing actuates the switch'actuating means,in combination with means within the casing including a float, saidswitch oper- 15 ating means connected to and communicating the movementof said float to the exterior of the casing whereby changes in the waterlevel in the boiler actuatet'he switch.

19. In combination, a casing, closure on one end of the casing,a-pressure responsive bellows secured to said closure over said apertureand extending within the casing, a float secured to the inner end of thebellows, a

an apertured 20 rod connected to the bellows and to the oat and' 25 walland means for securing said open end, of

the bellows to said wall whereby the bellows,4 the oat and therod are'supported by the wall, closed end `axially thru the bellows and thrusaid wall and means mounted exterior of ,said casing adapted to be, 4o

the free end of said rod. A

21. A device operated by changes in `water level 'and pressure,comprising-a pressure responsive element,'a float supported by saidelement, means actuated by the oat in response operated by axial andtransverse `movement of to changes in liquid level, ysaid means beingflxedly.` vsecured to the pressure responsive element whereby changes inpressure actuate said means independently of change in liquid level.

22. In combination, a water level casing having an apertured wall, apressure responsive bellows within the casing secured tothe wall,.afloat secured to the bellows, a rod secured to the iloat and thereby tothe bellows and extending thru the apertured wall, and a switch mountedon said casing adjacent the free end of` said rod and adapted to beoperated thereby. 23. A combined pressure and oat actuated switchmechanism for boilers, comprising a water level casing, a pressureresponsive device and a float within the casing,Y anelectric switchmechanism including a mercury switch tube suspended in arpivoted cradle,a unitary means for moving the tube into open and closed/ positions,said means being connected to the pressure re-v sponsive device andiloatl on the interior of the casing whereby change in pressure orchange in water level will actuate said switch.

'24. A combined pressure and oat actuated 70 mechanism for boilers,comprising a casing provided with means for communicating with theinterior of a boiler above and below the water level thereof, anelectric switch mechanism including a mercury switch tube pivotallysupported by said casing, unitary operating means for moving the switchtube into open and closed positions, a pressure responsive device of thebellows-type secured to the inner wall of the casing and a float withinthe casing, said float and said device being connected together and tosaid switch operating means whereby either change in pressure or changein water level or both will move said operating means to actuate saidswitch.

25. In a mercury tube switch having but two moving parts, a support, acradle freely suspended on a pivot in said support, a mercury tuberesiliently clamped in said cradle and adapted to hang in asubstantially horizontalv horizontal position below said pivot, apivoted rod, float means on one end of said rod for turning the sameabout its pivot to bring the free end thereof into engagement with .saidtube to thereby actuate the switch, means for moving said rod and itspivot longitudinally, and means on the rod for engaging said cradleduring said longitudinal movement to thereby actuate the switch.

27. In a water level responsive control, a float having a cylindricalshape, means for resiliently supporting said iioat in a horizontalposition whereby it may have universal movement, said meansy comprisinga, cylindrical bellows having onone end a centrally apertured plate forxedly mounting the same and having the free end sealed to the oat, andswitch means carried by said float. i

28. In a water level responsive control, a liquid chamber having anapertured `rwall, means for connecting said chamber to a liquidcontainer and for providing communication therewith whereby the liquidlevel of a container may be transmitted to the chamber, a, oat in saidchamber, means for mounting the`oat for completely universal movement,said oat mounting means` comprising a bellows having one end xedlymounted on said apertured wall and covering the vaperture thereinthereby providing accessY to the interior of said bellows from outsideof the chamber, the

free end of said bellows being connected to saidV iloat and switch fmeans operatively associated with said oat whereby to be actuated bythey,

change in liquid levelr in the chamber.

29. In a water level responsive control, a'chamber, pipe meansv forconnecting said chamberto a water boiler whereby the water level of theboiler maybe transmitted Vto the chamber,` a removable wall forsaidchamber, 'a horizontal munication with the atmosphere and switch'means adapted to be operated by said float as it changes position withthe change in water level.

30. In a liquid level responsive control, a chamber adapted forconnection with a variable level liquid supply whereby the liquid levelmay be reflected in the chamber, said chamber having an apertured endwall, a horizontal cylinder Within the chamber having one end sealed tosaid wall whereby the aperture permits communication between theatmosphere and the interior of the cylinder, the opposite end of saidcylinder `being free, the portion of said cylinder adjacent the wallbeing deeply corrugated forming a bellows and the opposite or free endof the cylinder being closed whereby said cylinder acts as a float, andswitch means operatively associated with the cylinder whereby uponchange in liquid level the switch is actuated.

31. A switch actuating device comprising a iioat and a cylindricalbellows open at one end to the atmosphere and closed at the other end bya wall of said float.

32. In a water level responsive device a float and means for resilientlysupporting the oat comprising an elongated horizontal bellows rigidlymounted at one end and secured to the oat at the other end, said bellowsserving to increase 'the buoyancy of the oat.

33. A switch operating unit for boilers comprising a bellows having itsinterior exposed to atmospheric pressure and compressible under pressureon its exterior surface, means for exposing the exterior surface of thebellows to boiler pressure, a. float carried solely by said bellowswhereby the float has substantially free universal movement and a.switch operatively associated with said float and bellows.

34. In a switch mechanism-adapted to be actuated by change in liquidlevel, a chamber having means for connecting with a liquid containerwhereby a change in liquid level in the container may-be reected in thechamber, an apertured wall for said chamber, a bellows within thechamber sealed at one end to said wall over said aperture whereby theaperture provides communication between the atmosphere and the interiorof the bellows, said bellows adapted to expand and contract on an axispassing through said wall, the other end of said bellows being free tovmove in any direction and a iloat secured to said other end wherebyupon any change in water level the float is adapted to move at an angleto the axis of the bellows, said oat being secured

